Eventide ARGUS 5000 - Minimum Safe Altitude Display

Minimum Safe Altitude Display
The information in the lower left corner of the lower window gives a minimum safe
altitude figure in feet above MSL (mean sea level). The display format is the same
as that on the sectional charts: The larger number is thousands of feet, the smaller is
\^j hundreds. 55 means 5,500 feet. The number is calculated from a database of sectional
chart grid square altitudes, and is intended to provide information that will help you
maintain an altitude that is comfortably above terrain and obstructions. There are
two features of this display that give you the information needed:
! The number itself. This is the Minimum Elevation Figure for charted
obstruction and terrain clearance determined by the Argus plus a one thousand
foot margin.
! Whether "MSL" (Mean Sea Level) is in reverse video. Reverse video
indicates that there is higher terrain or obstructions within a certain distance
of your aircraft.
The number itself is a composite determined from sectional grid squares surrounding
your present position. The Argus looks at the MEF (Maximum Elevation Figure) of
. ; your present sectional grid square, and also at the MEF of other grid squares near
your present position. If the range displayed on the Argus is greater than 10 miles,
then the MEF of any grid square within 10 miles of your present position is
considered. If the range displayed on the Argus is 10 miles or less, then only grid
squares which have any portion within the display range are considered.
Once the Argus determines which grid squares are "near" by this definition, it simply
takes the highest MEF in the group and adds one thousand feet as an additional
margin. Therefore, if you fly at or above this displayed altitude, you will clear charted
obstructions and terrain by at least one thousand feet.
July 1999 Argus 5000/7000 Ver. 5.xx Reference Manual Part#141003 21